You saw the story yesterday. Perhaps you were privy to some of the actual details that happened thanks to the original report that the confrontation between Bryce Harper and Rob Manfred was “heated”. By this point, you know.
MLB wants a salary cap in the next collective bargaining agreement.
Rob Manfred is making rounds to all the clubhouse to talk about economic issues in the game, presumptively to gauge their interest in a salary cap. It’s highly unlikely that he is using the term explicitly, otherwise he wouldn’t be good at his job.